Slurry process for hydrorefining petroleum crude oil

ABSTRACT

A CATALYTIC SLURRY PROCESS FOR HYDROREFINING A HYDROCARBONACEOUS CHARGE STOCK CONTAINING HYDROCARBONINSOLUBLE ASPHALTENES. THE SLURRY IS A MIXTURE OF THE CHARGE STOCK AND FROM ABOUT 1.5% TO ABOUT 25.0% BY WEIGHT OF FINELY-DIVIDED SOLID PARTICLES OF NONSTOICHIO METRIC VANADIUM SULFIDE. THE PROCESS IS EFFECTED CONTINUOUSLY, AND PREFERABLY IN AN UPFLOW SYSTEM WHEREIN THE SLURRY IS INTRODUCED AT A LOWER PORTION OF A REACTION CHAMBER, AND THE PRODUCT EFFLUENT WITHDRAWN FROM AN UPPER PORTION.

United States Patent 3,558,474 SLURRY PROCESS FOR HYDROREFIN IN G PETROLEUM CRUDE OIL William K. T. Gleim, Island Lake, and John G. Gatsis, Des Plaines, Ill., assignors to Universal Oil Products Company, Des Plaines, 11]., a corporation of Delaware N0 Drawing. Filed Sept. 30, 1968, Ser. No. 763,923

Int. Cl. C10g 13/02 US. Cl. 208-108 Claims ABSTRACT OF THE DISCLOSURE APPLICABILITY OF INVENTION The invention described herein is adaptable to a process for the conversion of asphaltene-containing petroleum crude oil into lower-boiling hydrocarbon products. More specifically, the present invention is directed toward a slurry-type catalytic process for continuously converting atmospheric tower bottoms products, vacuum tower bottoms products (vacuum residuum), crude oil residuum, topped crude oils, coal oil extracts, crude oils extracted from tar sands, etc., all of which are sometimes referred to as black oils, and which contain a significant quantity of asphaltic material. In particular, the process described herein atfords a high degree of asphaltene conversion to hydrocarbon-soluble products, while simultaneously effecting a substantial conversion of sulfurous and nitrogenous compounds to reduce the sulfur and nitrogen concentration of the charge stock.

Petroleum crude oils, particularly the heavy oils extracted from tar sands, topped or reduced crudes, and vacuum residuum, etc., contain high molecular weight sulfurous compounds in exceedingly large quantities. In addition, these black oils contain excessive quantitiesof nitrogenous compounds, high molecular weight organometallic complexes comprising principally nickel and vanadium, and asphaltic material. Asphaltic material is generally found to be complexed, or linked with sulfur and, to a certain extent, with the organometallic contaminants. Currently, an abundant supply of such hydrocarbonaceous material exists, most of which has a gravity less than 20.0 API at 60 F., a significant quantity having a gravity of less than 10.0 API. This material is generally further characterized by a boiling range indicating that by volume, and generally more, has a normal boiling point above a temperature of about 1050 F.

The process of the present invention is particularly directed toward the catalytic conversion of black oils into distillable hydrocarbons.

Specific examples of the black oils, illustrative of those to which the present invention is especially applicable, include a vacuum tower bottoms product having a gravity of 7.1 API at 60 F., containing 4.05% by weight of sulfur and 23.7% by weight of asphaltenes; and, a vacuum residuum having a gravity of 8.8 API at 60 F., containing 3.0% by weight of sulfur, 4300 ppm. nitrogen and having a 20.0% volumetric distillation temperature of 1055 F. The present invention affords the conversion of the majority of such material, heretofore having been believed virtually impossible, The principal difiiculty re sides in the lack of a technique which would afford man catalytic composites the necessary degree of sulfur sta bility, while simultaneously producing lower-boiling prod ucts from the hydrocarbon-insoluble asphaltic material This asphaltic material consists primarily of high molecu lar weight, nondistillable coke precursors, insoluble i: light hydrocarbons such as pentane or heptane.

Heretofore, in the field of catalytic processing of sucl material, two principal approaches have been advanced liquid-phase hydrogenation and vapor-phase, or mixed phase hydrocracking. In the former type of process, liquii phase oil is passed upwardly, in admixture with hydrogen into a fixed-fluidized catalyst bed. Although perhaps effec tive in converting at least a portion of the oil-solubl organo-metallic complexes, this type process is relativel ineffective with respect to asphaltics which are disperser within the charge, with the consequence that the prob ability of effecting simultaneous contact between the cata lyst particles, the hydrogen necessary for saturation am the prevention of coke formation, and the asphaltic mole cule is at best remote. The retention of unconverted as phaltics, suspended in a free liquid phase oil for an ex tended period of time, results in additional flocculatioi and agglomeration. Some processes have been describei which rely primarily upon cracking in the presence 0 hydrogen and a fixed-bed of a particulate solid catalyst The latter rapidly succumbs to deactivation as a resul of the deposition of coke and metallic contaminants there on. This type process requires an attendant high-capacit regeneration system in order to implement the proces on a continuous basis. Briefly, the present invention in volves a method whereby the asphaltic material and cata lyst are maintained in a dispersed state within a princi pally liquid phase rich in hydrogen. The asphaltic ma terial is capable of intimate contact with the catalyst thereby effecting reaction between the hydrogen ant asphaltic material; the liquid phase is itself dispersed ir a hydrogen-rich gas phase so that the dissolved hydroger is continuously replenished.

In addition to asphaltenes, sulfurous and nitrogenou: compounds, crude oils contain greater quantities of metallic contaminants than are generally found in lighter hydrocarbon fractions such as gasoline, kerosene, light gas oil, etc. A reduction in the concentration of the organometallic contaminants, such as metal prophyrins, is not easily achieved, and to the extent that the same no longer exert a detrimental effect with respect to further processing. When a hydrocarbon charge stock containing metals is subjected to a catalytic cracking process for the purpose of producing lower-boiling compounds, metals become deposited upon the catalyst employed, steadily increasing in quantity until such time as the composition of the catalytic composite is changed to the extent that undesirable results are obtained.

The principal object of the present invention is to provide a much more efficient process for hydrorefining heavier hydrocarbonaceous material, containing insoluble asphaltenes, utilizing a solid, unsupported catalyst. The term hydrorefining as employed herein, connotes the catalytic treatment, in an atmosphere of hydrogen, of a hydrocarbon fraction or distillate for the purpose of eliminating and/or reducing the concentration of the variou: contaminating influences previously described, accompanied by hydrogenation. As hereinabove set forth, metals are generally removed from the charge stock by deposition of the same onto the catalyst employed. This increases the amount of catalyst, actively shields the catalytically active surfaces and centers from the material being processed, and thereby generally precludes the efiicient utilization of a fixed-bed catalyst system for processing such contaminated crude oil. The present invention alves the use of a colloidally dispersed, unsupported tlytic material in a slurry process. The present process rrds greater yields of a liquid hydrocarbon product ch is more suitable for further processing without eriencing the difficulties otherwise resulting from the sence of the foregoing contaminants.

OBJECTS AND EMBODIMENTS ls hereinbefore set forth, a principal object of the pres invention resides in providing a process for hydroning petroleum black oils. A corollary object is to con hydrocarbon-insoluble asphaltenes into hydrocarbonrble, lower-boiling normally liquid products.

mother object is to effect removal of sulfurous and ogenous compounds by conversion thereof into hycarbons, hydrogen sulfide and ammonia.

t specific object is to effect the continuous decontamion of asphaltenic black oils by providing a slurry cess utilizing a solid, unsupported catalyst.

tnother specific object is to provide a novel composil of non-stoichiometric vanadium sulfide in which the nic ratio of sulfur to vanadium is in the range of from 1 to about 1.8:1.

herefore, in one embodiment, our invention encomses a process for hydrorefining a hydrocarbonaceous rge stock, containing hydrocarbon-insoluble asphalts, which process comprises reacting said charge stock 1 hydrogen, and in admixture with a vanadium sulfide, 1 hydrorefining reaction zone at hydrorefining condis selected to convert insoluble asphaltenes into lowering soluble hydrocarbons.

t more specific embodiment of our invention involves urry process for hydrorefining an insoluble asphaltenetaining hydrocarbonaceous charge stock which comes reacting a colloidal mixture of said charge stock from about 1.5% to about 25.0% by weight of non- :hiometric vanadium sulfide, having a sulfur to vanan atomic ratio of from 0.8:1 to about 1.8:1, with hygen in a reaction zone at hydrorefining conditions inling a reaction zone inlet temperature of from about C. to about 380 C., and a pressure within the range from 1500 to about 4000 p.s.i.g., and recovering a nally liquid product efiluent of decreased asphaltene :entration.

ther embodiments of our invention reside in the utili- 311 of particular operating conditions and techniques; e, as well as other objects and embodiments will bere apparent from the following detailed summary of invention.

SUMMARY OF INVENTION he unsupported catalyst, utilized in the slurry process be present invention, is a vanadium sulfide of non- :hiometric sulfur content. Through the use of the term supported, it is intended to designate a catalyst, or lytic component, which is not an integral part of a .posite with a refractory inorganic oxide carrier mall. That is, the catalyst is a vanadium sulfide without addition thereto of extraneous material. While the :ise atomic ratio of sulfur to vanadium is not known 1 accuracy, We have found that the catalytic vanadium .de, which is herein referred to as VS has a ratio of Jr to vanadium not less than 0821, nor greater than 1e.g., the numerical value of x in the foregoing irical formula lies in the range of 0.8 to 1.8. Furthere, this is not intended to mean that the vanadium de catalyst has but a single specific sulfur/vanadium but rather connotes a mixture of vanadium sulfides .ng sulfur/ vanadium mole ratios in the aforesaid range. lhile four oxidation states are known for vanadium, i, 4 and 5, Periodic Chart of The Elements, E. H. gent & Company, 1964, only three stoichiometric valum sulfides are sufficiently stable for identification. se are: monovanadium sulfide, VS; sesquivanadium Ldfi, V S and pentavanadium sulfide, V 3 Handbook of Chemistry and Physics, Chemical Rubber Publishing Company, 42nd ed., page 680, l9601961. Many nonstoichiometric vanadium sulfides have been identified in the literature, including, and possibly the most common, V8 commonly referred to as the tetrasulfide. Significantly, the vanadium sulfide we have found is not identifiable as any of the stoichiometric vanadium sulfides, or as V5 The principal utility of the nonstoichiometric VS resides in the conversion of hydrocarbonaceous material. While, as hereinbefore stated, and as hereinafter set forth in specific examples, the use of our nonstoichiometric vanadium sulfide in the conversion of asphaltic, high metals-containing hydrocarbon charge stock affords unusual advantages, it may be utilized in other hydrocarbon conversion processes which lend themselves to slurry-type processing. Such processes include dehydrogenation of paraffinic hydrocarbons, catalytic reforming of naphtha boiling range charge stocks, dehydrogenation of alkylaromatics, cracking of polynuclear concentrates such as light cycle stocks, the dealkylation of alkylaromatic hydrocarbons, etc.

In the preparation of nonstoichiometric VS of the present invention, we have found it convenient to initially prepare the nonstoichiometric VS vanadium tetrasulfide. Upon reduction in an atmosphere of hydrogen, the VS; is converted to the VS where x ranges from 0.8 to 1.8 as hereinbefore set forth. The Vanadium tetrasulfide is prepared by reducing vanadium pentoxide with sulfur dioxide and water to yield solid vanadyl sulfate trihydrate. The latter is treated with hydrogen sulfide at a temperature in the range of 250 C. to about 350 C.- i.e., 300 C.to form the vanadium tetrasulfide. The vanadium tetrasulfide is subsequently reduced in hydrogen at a temperature above about 300 C. to produce the catalytic VS having the aforesaid sulfur/ vanadium atomic ratios. Since substantially complete reduction of VS, to VS is desired, and the catalytic action of the latter within the slurry with the charge stock is enhanced when existing in finely-divided form, it is preferable to grind the vanadium tetrasulfide to about /200 mesh prior to reducing the same with hydrogen.

In view of the fact that the charge stock is reacted with hydrogen, being admixed therewith in an amount greater than 10,000 s.c.f./bbl., the reduction of the vanadium tetrasulfide is facilitated when it is slurried with the charge stock and hydrogen. Upon being heated to the desired reaction zone inlet temperature, prior to being introduced thereto, the tetrasulfide is reduced to the catalytic VS with the sulfur/vanadium mole ratios in the range of 0.8:1 to about 1.8:1. While the tetrasulfide can be reduced to VS prior to forming the colloidal slurry, the foregoing procedure is preferred since a savings in hydrogen is realized, and one step of the overall scheme is eliminated. In either event, it is understood that the catalytic vanadium sulfide is the reduced tetrasulfide, and not the latter prior to reduction. Furthermore, since V5,; is unstable above a temperature of 300 C., the reduction thereof with the hydrogen admixed with the charge stock is facilitated as the reaction zone inlet temperature of 325 C. to about 380 C. is attained.

The concentration of VS within the charge stock is at least 1.5 by weight thereof, calculated on the basis of elemental vanadium. Excessive concentrations do not appear to enhance the results, even with extremely contaminated stocks with very high asphaltene content. Therefore, the upper limit of the vanadium sulfide is about 25.0% by weight. The colloidal slurry is admixed with hydrogen in an amount of from 10,000 to 100,000 s.c.f./'bbl. of charge stock. Following suitable heat-exchange with various hot effluent streams, the temperature of the mixture is further increased to the level desired at the inlet to the reaction zone. Since the reactions being effected are principally exothermic, the

temperature of the effluent from the reaction zone will be considered higher than the inlet temperature. Therefore, the inlet temperature will be controlled in the range of from 325 C. to about 380 C. The residence time in the reaction zone is such that the effluent temperature is not higher than about 500 C. We have found that excellent results are attainable when the temperature gradient is 380 C. to about 450 C. The reaction zone is maintained under an imposed pressure greater than about 1000 p.s.i.g., and preferably at a level of from 1500 to about 4000 p.s.i.g.

Although the present process may be effected in an elongated reaction zone with the slurry and hydrogen being introduced into the upper portion thereof, the effluent being removed from a lower portion, an upflow system offers numerous advantages. A principal advantage resides in the fact that the extremely heavy portion of the charge stock has an appreciably longer residence time within the reaction zone, with the result than a greater degree of conversion is attainable, and incoming hydrogen will effectively strip lower boiling products therefrom. Also, the heavy, unconverted asphaltic material can bewithdrawn from the bottom of the reaction zone along with solid particles of vanadium sulfide. The liquid product effluent, containing distillable hydrocarbons, along with hydrogen, hydrogen sulfide, ammonia and a minor quantity of normally gaseous hydrocarbons, principally methane, ethane and propane, are removed from the top of the reaction zone. A hot flash system, functioning at essentially the same pressure as the reaction zone in a first stage, and at a substantially reduced pressure in a second stage, serves to separate the overhead product efiluent into a vapor phase, the principal portion of which boils below about 800 F. and a liquid phase boiling above about 800 F. The latter may be recycled to combine with the fresh charge stock, thereby serving as a diluent, or it may conveniently be employed to facilitate the introduction of fresh and/or regenerated catalyst to the reaction zone in admixture with the charge stock.

The principally vaporous phase passes into a cold high pressure separator (about 60 F. to 120 F.), wherein a hydrogen-rich gaseous phase is recovered and recycled, along with make-up hydrogen to supplant that consumed within the reaction zone. The normally liquid phase from the cold separator, containing some butanes, is generally subjected to fractionation to prepare a charge stock suitable for further processing.

With respect to the bottoms stream from the hot flash system, while this may be totally recycled to combine with the fresh hydrocarbonaceous charge, it is a preferred operating technique to withdraw a drag stream containing at least about 10.0% by weight of the catalyst employed. Any suitable means may be utilized to separate the solid catalyst from the liquid phase hydrocarbons, including filtration, settling tanks, a series of centrifuges, etc. A like quantity of fresh, or regenerated catalyst is then added in order to maintain the selected catalyst content of the slurry.

The catalyst withdrawn with the drag stream is separated, for example, by a series of filtration and methyl naphthalene washing techniques. Methyl naphthalene is employed to remove residual, soluble hydrocarbons from the catalyst sludge. Other suitable solvents include n-heptane, benzene, toluene, etc. The remainder of the catalyst sludge is burned in air to produce vanadium pentoxide which is reduced with sulfur dioxide and water to produce vanadyl sulfate. The regeneration procedure then follows the previously described preferred scheme for the preparation of fresh vanadium sulfide.

The following examples are introduced for the primary purpose of further illustrating the slurry process of the present invention, and to indicate the benefits afforded through the use thereof in the hydrorefining of asphaltenecontaining black oils.

Cir

6 EXAMPLE 1 A Boscan crude oil was processed continuously in upflow operation with a suspended vanadium cataly: The pertinent charge stock properties are given in t] following Table I:

Table I.Boscan crude oil properties API at F 8 Molecular weight 6E Heptane-insolubles, wt. percent l6 Sulfur, wt. percent 6 Nitrogen, p.p.m 652 Total metals, p.p.m. 14

A vacuum Engler Distillation indicated an initial bo: ing point of 535 F., a 30.0% by volume distillation ter perature of 910 F., with 41.0% being distillable about 1050 F.

Previous work with a batch process had proved su cessful where the catalyst was prepared in situ from 2 organovanadium compound. For the instant operatio therefore, the catalyst was produced in the reaction 201 by decomposing vanadyl acetylacetonate, dissolved methyl naphthalene, under a pressure of 3000 p.s.i.g. 1

. hydrogen-hydrogen sulfide (10.0% hydrogen sulfide). Tl

Boscan crude oil was processed at a temperature gradie: of 370 C. to 425 C. and a charge rate of 75 gran per hour. Hydrogen circulation was in the amount about 2.5 s.c.f./hr. At these conditions, heptane-insolub conversion was about 90.0%, as was the metallic co: taminant removal. Approximately 50.0% of the nitrogc and 60.0% of sulfur was removed, and the gravity i creased to 20.6 API. At the termination of this oper tion, an inspection of the reaction zone internals indicate a deposit of approximately As-inch thickness on thewall Analysis of this material further indicated that it cor tained about 12.0% by weight of unconverted asphaltene the remainder being principally vanadium and sulfur.

Although the degree of contaminant removal was e1 couraging during the initial phase of the operation, tl efliciency began declining, ostensibly due to the accumi lation of vanadium sulfide, having a sulfur to vanadiu: ratio of about 2.021, on the interior walls of the reactic vessel.

EXAMPLE II The procedure followed in the: foregoing Example was repeated with one exception: the quantity of cataly (as vanadium) was increased about 50.0%. Asphalter conversion was 83.0%, and 86.0% of the metals, 72.0. of sulfur and about 55.0% of nitrogen was removed. Tl apparent reason for no increase in conversion, or CO] taminant removal, at the higher catalyst concentratior was attributed to the deposition, once again, of vanadiui sulfide and coke onto the walls of the reaction vesse Seemingly, increasing the catalyst concentration serve only to increase the measurable thickness of the deposi EXAMPLE III Boscan crude oil was again processed in upflow fashiol charging grams/ hr. at a temperature gradient of 37C C. to 440 C. The pressure was 3000 p.s.i.g. and the hydrt gen recycle rate was 14 s.c.f./hr. (15,000 s.c.f./bbl. crude). In this particular instance, the reaction vessl F was ceramically lined with a titanium-based porcelai t on the walls as well as the screen placed near the of the vessel.

EXAMPLE IV or this series of operations, an aqueous solution of adyl sulfate was charged to the reaction zone in adture with the crude oil charge stock. The vanadyl ate solution had a specific gravity of 1.0528 at 60 F., contained 1.66% by weight of vanadium. Operating litions, at the outset, included a temperature gradient .75 C. to 420 C., a pressure of 3000 p.s.i.g., a hygen recycle rate of 84 s.c.f./hr. (90,000 s.c.f./bbl.), ude charge rate of 150 grams/ hr. and a catalyst solurate of 50 cc./ hr. After 22 hours of operation, about of the heptane-insolubles and 87.0% of the metals a converted. The gravity of the normally liquid prodefiluent had increased to 15.0 API from the 81 of the fresh charge stock.

t about 35 hours on-stream, a noticeable pressure was experienced across the reaction zone, and the )duction of charge stock and catalyst solution was ."nipted. After three hours of hydrogen circulation, charge was reintroduced at a rate of 75 grams/hr. the temperature gradient increased to 360 C. to C. At the termination of 167 on-stream hours, inent analyses of the normally liquid product effiuent :ated the results presented in the following Table II:

Table II.-Product analyses vity, API 21.5 tane-insolubles, wt. percent 0.21 ur, wt. percent 2.12 ogen, p.p.m. 3720 L1 metals, p.p.m. 9 illables, vol. percent 97.5

uring the next 24 hours, the charge stock was changed vacuum tower bottoms product having the properties :ated in the following Table III:

Table III.Vacuum tower bottoms properties vity, API 9.8 illables, vol. percent at 1050 F. 30.0 tane-insolubles, wt. percent 5.2 ur, wt. percent 3.06

ogen, p.p.m. 4030 L1 metals, p.p.m. 98

t the termination of 191 on-stream hours, analyses he normally liquid product eflluent indicated the lts presented in the following Table IV:

Table IV vity, API 19.6 tane-insolubles, wt. percent 0.14 ur, wt. percent 1.17 ogen, p.p.m. 3000 ll metals, p.p.m. 9 illables, vol. percent 90.5

he charge stock and catalyst solution introduction ceased, but hydrogen circulation continued for an tional period of about 42 hours. Heaters and hydrocompressor were shut off, and depressuring was In. The reaction zone would not depressure com :ly. Toluene was charged at a rate of 200 cc./hr. a temperature of 150 C.; this was followed, after .ours, by methyl naphthalene for 18 hours at 200 C. iene was injected for an additional six hours at a )erature of 75 C. This procedure permitted the plete depressuring of the reaction zone which upon g opened, was found to be completely packed with lid material removable only by drilling. The recovered :rial was treated with methylnaphthalene, to we organic soluble material, and subsequently with dine. The individual washings were precipitated with ane, the pyridine-washed precipitate being recovered 8 in an amount of about grams. The solids contained no sulfur, but 8.1% by weight of nitrogen and about 5.0% by weight of vanadium.

The plugging of the reaction zone, evidenced by the pressure differential, is attributable primarily to the accumulation of unconverted heptane-insoluble asphaltenes in the zone. This apparently arises as a result of the phase separation which occurs during the decomposition of the vanadyl sulfate in the presence of the asphaltics. This appears to create an environment conducive to the formation of asphaltic complexes at the reaction conditions employed.

EXAMPLE V The charge stock utilized in this example was the previously described vacuum tower bottoms. Vanadium pentoxide was reduced in sulfur dioxide and water to prepare vanadyl sulfate trihydrate. The latter was treated in a hydrogen sulfide atmosphere at 300 C. and the resulting vanadium tetrasulfide was ground to about 200 mesh. 832 grams of the tetrasulfide was added to 1200 grams of the vacuum tower bottoms in a colloid mill over a period of about four hours. The reaction zone was preloaded with about 255 grams of the oilvanadium tetrasulfide mixture, and the unit was pressured to about 3000 p.s.i.g. A hydrogen recycle rate of 14 s.c.f./hr. (about 30,000 s.c.f./bbl.) was established.

The block-heater temperature was raised to 100 C., and held for one hour, after which the block-heater temperature was raised to 300 C. At this point the vacuum tower bottoms, with the vanadium tetrasulfide, was introduced into the heater, in admixture with the circulating hydrogen stream. The temperature gradient, as measured from the reaction zone inlet, to the outlet Was controlled at about 320 C. to 385 C., by controlling the furnace (black-heater) skin temperature at about 410 C. The charge rate was 75 ml./hr. and makeup hydrogen in an amount of about 4.75 s.c.f./hr. was added to the process.

Greater than 99.0%- heptane-insolubleconversion was attained, and the operation was terminated at 116 onstream hours voluntarily, without experiencing noticeable pressure drop across the reactor. After charging 1200 grams of the vacuum tower bottoms, analyses indicated about 0.03% by weight of asphaltenes in the product efiluent, less than 5 p.p.m. of vanadium complexes (as elemental vanadium) and about 6 p.p.m. of nickel. The gravity of the normally liquid product had increased to 16.5. A material balance, with respect to the vanadium introduced as catalyst, indicated very little loss by way of deposit on the walls of the vessel.

The foregoing specification clearly indicates the method by which the present invention is effected. Data presented illustrates the benefits and advantages resulting from the.

use of our invention in a process for hydrorefining asphaltene-containing hydrocarbonaceous black oils.

We claim as our invention:

1. A process for hydrorefining a hydrocarbonaceous charge stock, containing hydrocarbon-insoluble asphaltenes, which process comprises reacting said charge stock with hydrogen, and in colloidal admixture with nonstoichiornetric vanadium sulfide, having a sulfur to vanadium atomic ratio of from 0.8:1 to about 1.8:1 and excluding VS and V S in a reaction zone at hydrorefining conditions selected to convert insoluble asphaltenes to lower-boiling soluble hydrocarbons.

2. The process of claim 1 further characterized in that said hydrorefining conditions includes a temperature of from about 325 C. to about 500 C. and a pressure greater than about 1000 p.s.i.g.

3. The process of claim 1 further characterized in that said charge stock is admixed with vanadium sulfide in an amount of at least 1.5% by Weight, 'as elemental vanadium.

4. The process of claim 1 further characterized in that hydrogen is present in said reaction zone in an amount of at least about 10,000 s.c.f./bbl. of said charge stock.

5. A slurry process for hydrorefining an insoluble asphaltene-containing hydrocarbonaceous charge stock which comprises reacting a colloidal admixture of said charge stock and from about 1.5% to about 25.0% by weight of nonstoichiometric vanadium sulfide, having a sulfur to vanadium atomic ratio of from 0.811 to about 1.8:1 and excluding VS and V 8 with hydrogen in a reaction zone at hydrorefining conditions including a pressure of from 1500 to 4000 p.s.i.g. and a reaction zone inlet temperature of from 325 C. to about 380 C.,

10 and recovering a normally liquid product efliuent decreased asphaltene concentration.

References Cited 5 UNITED STATES PATENTS 3,161,585 12/1964 Gleim et al 2082l 3,074,879 l/1963 Weekman 2081l 3,147,207 9/1964 Doumani 208ll 10 DELBERT E. GANTZ, Primary Examiner A. RIMENS, Assistant Examiner US. Cl. X.R. 15 208213, 216 

